Tarar said the authorities were waiting for a report on the incidents.

"We will hold a meeting on this tomorrow," she said. "After that, we will direct the provincial governments on how to save the lives of those who are out to save lives of others."

Speaking to Al Jazeera, Moeed Yusuf of the United States Institute of Peace (USIP), Washington DC, said: "The real problem is that the state's capacity in the rural areas has shrunk to a point where it can simply cannot defend or protect its own citizens and communities."

The Karachi shootings come just days after the World Health Organisation (WHO) said that Pakistan's northwestern city of Peshawar was the world's "largest reservoir" of the polio virus.

According to WHO, Pakistan recorded 91 cases of polio last year compared with 58 in 2012.

By contrast, the country's neighbour India last week celebrated three years since its last polio case.

Repeated attacks

Polio can permanently paralyse or kill victims within hours of infection.

Intensive vaccination campaigns have almost eradicated the disease worldwide.

Pakistan is one of only three countries in the world where polio remains endemic, along with Afghanistan and Nigeria.

Efforts to eradicate it have been seriously hampered by the repeated targeting of vaccination teams in recent years.

Many teams only travel with police protection.

Last year there were more than 30 attacks on polio teams.

Pakistani Taliban commanders have forbidden vaccination teams to access some areas. A handful of religious leaders have also denounced the campaign as a plot to sterilise Muslim children.

"This is essentially political rhetoric mixed with religious edicts which absolutely makes no sense to a rational mind," Yusuf of USIP told Al Jazeera.

"There is a whole new political twist to this after the controversy around the raid that killed [al-Qaeda chief] Osama bin Laden [in the Pakistani city of Abbotabad] and this doctor who was apparently running a fake polio campaign being indicted."